Get listing

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint and openWorldHint, so 'Read-only' largely restates structured data rather than adding it. The description does add that the returned data is 'normalized' and that only one listing is fetched, but says nothing about failure modes, missing ids, or rate limiting.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three short sentences, front-loaded with the action and resource; every clause carries information (action, target, return, invocation, safety) with no filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

No output schema exists, so the description carries the return burden and largely meets it by saying it returns 'normalized details' of one listing. It could be more specific about what fields the normalized payload contains, which is the only real gap for this two-parameter read tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3, but the description adds a genuinely useful semantic the schema lacks: the two optional parameters are alternatives ('provide either `id` or `url`'), clarifying that one is required despite neither being marked required.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a concrete verb and resource ('Open a single Kleinanzeigen listing') plus the outcome ('return its normalized details'), which distinguishes it from the plural sibling search_listings implicitly via 'single'. It never names the sibling, so differentiation is inferred rather than stated.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied by 'single listing' versus the search sibling, and the 'either `id` or `url`' note signals one way to invoke it. There is no explicit when-to-use/when-not or direct reference to search_listings for the multi-result case.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.